Hp 17 dar62cmb6a0 board charging no power

[mcplslg123]

Ram voltage will come only after turning on. Since RSMRST# is 0, it wont turn on. What is the resistance on RSMRST# pin of SIO?? Check BATLOW#.

[NConstantinou]

Thanks for your reply,

i just have noticed that i do not have +pwrscr. i do have 19v on EC12 BUT on PR50 i don't but there is continuity.
The resistance of RSMSRT# is 2.2k.
r494 batlow# ON SIDE IS 29K AND THE OTHER 38K.



THANKS

[NConstantinou]

Correction.

On Pr50 on +PRWSRC side i get 19v and on the other side 0.02v which i assume is correct.
what i noticed is that at the points where i am suppose to have +3v i have nothing.
i that due to RSMRST#!

thanks

[mcplslg123]

Why you are investigating PR50 when ACDET is ok?? I asked for voltage on BATLOW#, not resistance. However, resistance on RSMRST# seems bit low to me. I think should be close to 10K or higher. What about LID_EC# voltage??

[NConstantinou]

BATLOW# i measured at PM_BATLOW# and i get 0v.
The LID_EC voltage is 3.3v

[NConstantinou]

I have found out that i do not have +3vsus.
Does this come from pu6 slg55448vtr ic!

Also u31 bios does not have any voltage on any pin

thanks

[mcplslg123]

@NConstantinou, your understanding of schematics seems poor to me and that's the case with many members as understanding of schematic takes time. On this architecture, your 3V/5V rail are both in suspended form-meaning they will rise after turn on only. SUS rails apeear after turn on only. U31 bios chip is powered by +3V_S5 rail and thats in suspend mode, so wont be available in off mode.

Check SIO requirements deeply and you may get a clue.

[NConstantinou]

Dear mcplslg123

i am not expert in laptops because i don't know the exact sequence
of the power.
as far as the sio i have changed it and i checked the follwing.

ACIN 3.3v
AC_RCIN 3.3v
S5_ON 3.3v
Vcc 3.3v
AVcc 3.3v
NBSWON1# 3.3v
AC_PRESENT 3.3v

this is what i know. do i need to check other pins!
is there any way to find out the requirements of kb3940q s5 stage!
i couldn't find anything in google

thanks

[mcplslg123]

HWPG,Pin14 OF ENE3940?? ECRST# status.

[NConstantinou]

Ecrst# 3.3v
hwpg 0v

do pins 77 and 78 must have 3.3v!

Thanks

is hwpg suppose to be 3v!

Thanks

[NConstantinou]

Now on pr207 i have 3.3v but the side that goes to pin4 of pu9 i have 0v.
Resistor is 10k.pr208 does not exist on board.

[mcplslg123]

PIN77/78 should be 3.3V as its part of smbus. Your problem is HWPG. Type HWPG in schematic and check everything where it goes. You may need to cut tracks to isolate a particular IC from HWPG and then check whether it rises to 3V. The job is not easy and require delicate cuts else you may damage the track underneath.

I'll suggest you to take it to some professional so that mb is saved. Other option is to change all the ic, one at a time, to see if HWPG rises(ALL ic's connected to HWPG).

[mcplslg123]

Originally Posted by NConstantinou

Now on pr207 i have 3.3v but the side that goes to pin4 of pu9 i have 0v.
Resistor is 10k.pr208 does not exist on board.

HWPG is a pullup voltage and it will pull the voltage from +3VS5 only when evrything is good in HWPG. Its not pulling up the voltage as it senses some problem in HWPG.

[NConstantinou]

thanks for your reply,
i have one question for you.
Till now we decided that it is HWPG problem because this voltage doesn't appear BUT is generated by different IC's.
one of those ic's is PU10 pin4.
My question is!
I HAVE CHECKED PATH OF HWPG AND THERE IS CONNECTIVITY TO ALL POINTS.
can i inject voltage to that rail! (3v) and check all path of HWPG rail to see if i have the 3v at all points!



Thanks again

[NConstantinou]

I missed one point and i think i am correct.
i did inject 2.8v on D12 using power supply.
voltage dropped to 2v with .33A.
All points that have HWPG had the 2v exceptPU16 pin 3 0v.
Now pin 3 is GFX_HWPG which is connected to PR300 10k resistor and then give 3v. there i have 0v. The resistor measures 10k.

can i increase Amps and if yes what is the maximum.

thanks

[mcplslg123]

Wrong approach again. GFX_HWPG will rise at the very end of power sequence while posting. So you wont get voltage there without mb turning on properly. You cant isolate HWPG problem with voltage injection. I've already listed the ways to isolate HWPG problem. If you find it too difficult, then once again i'll suggest to seek help from a professional. Every problem cant be solved online. Having physically the board on your table makes all the difference.I tried my level best to help you but you need to do your part. Forum only helps in getting a clue but the physical repair has to be carried by the person having the board.